Patent GB-190819054-A (GB)
Title: Improvements in or connected with Current Collectors and Control Systems of Electrically Propelled Vehicles.
Inventor: BEACH HOWARD LINCKLEY
Filed: 1908-09-10
Granted: 1909-02-04
Abstract: 19,054. Beach, H. L. Sept. 26, 1907, [date applied for under Section 91 of Patents &c. Act, 1907]. Motor control systems.-In electric railways on the overhead - conductor system using motors adapted to work with either direct or alternating current, separate collectors are used for the direct and the alternating current, and means are provided for facilitating the raising and lowering of the alternating-current collector, and for causing it to be lowered automatically if the transformer circuit should be broken by the wheels of the vehicle leaving the track or from any other cause. The apparatus is described in association with a motor control system comprising a master controller 58, an automatic change-over switch 53 actuated by electro-magnets 54, 55, electro-magnetic switches 32, 41, 42, 43, 44, and resistances 33 to 36 for controlling the motors when direct-current is being used, electro-magnetic switches 45 to 52, a transformer 27, and preventive coils 97, 98, 107, arranged as described in Specification No. 12,493, A.D. 1906, for controlling the motors when alternating current is being used, and electro-magnetic switches 37 to 40 for putting two pairs of series motors 1 ... 4 in parallel for alternating current and in series for direct current. The alternating- current collector 12, which is of the pantograph type, is normally held up by a spring 15, but can be lowered by admitting compressed air from a reservoir 114 to a cylinder 18 by means of an electromagnetically actuated valve 20. When lowered, the collector is held down by the engagement of a spring hood on the bow 14 with a catch 117, which can be released by admitting air to a cylinder 19 by means of an electro-magnetically actuated valve 21. A battery 59 supplies current for working the valves and the various switches. With the various devices in the position shown, the closing of a switch 60 releases a catch 63 and allows an overload switch 24 to close, thus completing a relay circuit through the coil of a main circuit closer 23, and causing the main circuit through the transformer 27 to be completed. A branch circuit to earth from one of the taps of the transformer then raises a switch 57 and completes a relay circuit through the electro-magnet 55 of the change-over switch 53, causing it to be set in the position shown. The movement of the controller 58 to its first 'on' position a completes relay circuits through points 80, 83, 86 to the switches 37, 38, 39, thus putting the motors in parallel, and also through points 91, 93 to the switch 52, which completes the circuit to the motors from the first tap of the transformer. Successive movements of the controller close successively the other transformer-tap switches, four being closed in succession before the first is opened, and so on. If the main circuit through the transformer should be broken from any cause, the switch 57 is no longer held up and drops on to contacts 110, thus completing a circuit from the battery through the coil of the valve 20 and causing the lowering of the collector. The main circuit can be broken at will by moving a hand switch 67 to break the relay circuit through the coil of the main circuit closer 23. The collector can be allowed to rise again by means of a hand switch 74, which can be moved to break the circuit through the coil of the valve 20 and complete it through the coil of the valve 21. When passing on to a continuouscurrent section, the driver lowers the alternating- current collector, and raises the continuous current collector 11 by band. A branch circuit to earth then moves a switch 56 on to points 120 and completes a relay circuit through the electro-magnet 54 of the change-over switch 53, thus moving it from position x to position y ready for continuous-current working. The first movement of the controller then closes the switches 38, 40 to put the motors in series, and also closes the switch 32 which completes the main circuit through the resistances to the motors. Successive movements of the controller then operate the switches 41 ... 44 to cut out the resistances.